Heres a build that works better...

8 scv build depot
10 scv build rax
12 scv build vespine

Then do whatever you normally do, gradually teching to nuke.

Build sci on an island/your natural, whatever.

Drop on their natural / main if you can do it, EMP if toss, and that expo is done, at the same time move an attack in, with siege tanks near the cliff / base to cover you